Upgrade package:http to 0.11.3+17.

Change-Id: Ic2eb67fac0c361be458d44201f4d573bcfac9221
Reviewed-on: https://dart-review.googlesource.com/64080
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>
Commit-Queue: Devon Carew <devoncarew@google.com>
diff --git a/DEPS b/DEPS
index ba08f05..91d57a5 100644
--- a/DEPS
+++ b/DEPS
@@ -89,7 +89,7 @@
   "http_multi_server_tag" : "2.0.4",
   "http_parser_tag" : "3.1.1",
   "http_retry_tag": "0.1.1",
-  "http_tag" : "0.11.3+16",
+  "http_tag" : "0.11.3+17",
   "http_throttle_tag" : "1.0.2",
   "idl_parser_rev": "5fb1ebf49d235b5a70c9f49047e83b0654031eb7",
   "intl_tag": "0.15.2",